The present invention relates to a wildcat (chainwheel) for a windlass used for dropping or hoisting an anchor into a marine vehicle.
In boats of ten meters or more length, the anchor weight is so great that a single person cannot pull it easily and therefore an electrical, hydraulic (or manually-driven) windlass is used to hoist the anchor into the boat. The main component of a windlass is a metal chainwheel also called a wildcat for hoisting or dropping down the chain that the anchor is connected to, or the rope, which is a pulley-like member. The wildcat is engaged to a rotating shaft from its center and when this shaft is rotated, the chain and the anchor is hoisted into or dropped down of the boat through the bearing surface.
The present invention relates to a wildcat mechanism of windlasses suitable for chained-type anchors to be hoisted into or dropped down of the boat. Anchor chain wildcats comprise indents and protrusions formed on the bearing surfaces that are covered on the chain. Therefore, when the wildcat is rotated, the chain links obtain the mechanical support sufficient for carriage through the indents and protrusions, and thus they are hoisted into the boat or released from the boat. However, as conventional metal or metal casting wildcats cannot retain the chain links properly, there emerge vibrations, leaping and noises during usage and as a result of them a great noise emerges and impact on the links is unavoidable.
The wildcat disclosed in U.S. Pat. No. 7,520,490, the entire contents of which is incorporated herein by reference, can be considered as an example of a conventional type wildcat. In FIG. 2 of U.S. Pat. No. 7,520,490, the entire contents of which is incorporated herein by reference, the indents (32) and protrusions (33) that have been formed on the bearing surface are shown. These indents and protrusions cannot retain the chain links properly and therefore causes noise and cannot prevent the links from vibrating and leaping. The wildcat disclosed in U.S. Pat. No. 7,520,490, the entire contents of which is incorporated herein by reference, has not been made of a material which can provide an ease of transfer on the chain.